White matter fiber tractography (WMFT) refers to a class of techniques that use data obtained with diffusion magnetic resonance imaging (dMRI) to map axonal fiber bundles within white matter of the brain. WMFT, which can be obtained in three dimensions for the whole brain in vivo in a completely noninvasive manner, has revolutionized the study of structural brain connectivity. In fact, WMFT is being used clinically for the planning of neurosurgical interventions so that surgeons can preserve critical brain functions. However, the various WMFT techniques differ in accuracy and practicality.
Human applications in clinical settings have favored a technique based on diffusion tensor imaging (DTI), referred to as DTI fiber tractography (DTI-FT). While DTI-FT is readily implemented on standard clinical magnetic resonance imaging (MRI) scanners, DTI-FT suffers from substantial inaccuracies because it is incapable of detecting the intersection of two or more fiber bundles within an imaging voxel. This so-called “fiber crossing problem” has led to the development of several alternative WMFT approaches. However, due to various challenges with implementation, these approaches have not replaced DTI-FT for most clinical applications.